The present invention relates generally to engines and more particularly to a high efficiency hydraulic engine.
Engine efficiency continues to be a primary concern in engine design particularly given limited supplies of hydrocarbon fuel, detrimental effects of hydrocarbon pollution, and increasing costs of extracting hydrocarbon fuel. Current engines including internal combustion engines and diesel engines suffer many disadvantages including piston ring and cylinder wear, heat loss, and specific compression ratios. Internal combustion or pressurized gas assisted hydraulic engines have been proposed in the art to provide more efficient energy conversion. However, conventional designs disadvantageously include pistons and cylinders.
A hydraulic engine is disclosed in U.S. Pat. No. 3,983,699. An is oil pressure chamber is coupled to the input of a turbine for driving the turbine with hydraulic fluid under pressure. A lower cylinder has a piston movably mounted therein for movement in axial directions. The output end of the lower cylinder is coupled to the oil pressure chamber. An upper cylinder has a piston movably mounted therein for movement in axial directions and coupled to the piston of the lower cylinder for movement therewith. A hydraulic fluid supply is coupled to the output end of the lower cylinder for supplying hydraulic fluid to the lower cylinder. A fuel and air mixture supply is coupled to the output end of the upper cylinder for supplying a fuel and air mixture to the upper cylinder. A coupling device couples the output end of the upper cylinder to the input end of the lower cylinder whereby movement of the piston from the input end to the output end in the upper cylinder compresses the fuel and air mixture and supplies it to the input end of the lower cylinder. A spark device in the input end of the lower cylinder explodes the fuel and air mixture in the lower cylinder thereby moving the piston thereof from the input end to the output end to compress the hydraulic fluid in the output end thereof and supply it to the oil pressure chamber and thence to the turbine to drive the turbine.
U.S. Pat. No. 4,097,198 discloses an internal combustion assisted hydraulic engine. The engine utilizes two sets of hydraulic cylinders connected to a shaft so as to be alternately pressurized as the shaft is reciprocally driven by a pair of conventional internal combustion chambers. The outlets of all hydraulic cylinders are connected to a common output line via valves. During each power stroke certain of the hydraulic cylinders being pressurized are selectively disconnected (depressurized) from the output line. This effectively decreases the load on the driving chamber, and insures a relatively constant, high pressure hydraulic fluid output level despite changes in supplied force during each power stroke. The selective cylinder disconnection may be implemented programmatically in response to changes in engine parameters such as combustion pressure.
A fuel/hydraulic engine system is disclosed in U.S. Pat. No. 6,551,076. A fuel engine having a cylinder and piston includes a fuel injector, a spark plug, and an intake valve controlled by an intake solenoid. A fuel engine piston is physically located and attached by a shaft to a hydraulic work piston.
What is needed is a hydraulic engine that overcomes the disadvantages of the prior art. What is also needed is a hydraulic engine that has a floating piston. What is further needed is a hydraulic engine that does not require a cooling system. What is also needed is a hydraulic engine that provides for an increased number of turbine shaft revolutions per combustion chamber explosion.